<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style>
	div{
		width:318px;
		/* height:318PX; */
		border:1px solid red;
		
		/* 给此div设置定位，仅仅是为了以他为目标进行绝对定位，
		因此无需给他设置偏移量。*/
		position:relative;
	}
	p{
		position:absolute;
		bottom:40px;
		width:100%;
		background-color:#fff;
		text-align:center;
	
	}
		
	



</style>
</head>
<body>
	<div>
		<img src="../images/3.jpg"/>
		<p>苍老师到此一游</p>
	</div>



</body>
</html>